The G-protein coupled receptor SRX-97 is required for concentration dependent sensing of Benzaldehyde in Caenorhabditis elegans

AbstractThe G-protein (heterotrimeric guanine nucleotide–binding protein)–coupled receptors in the olfactory system function to sense the surroundings and respond to various odorants. The genes encoding for the olfactory receptors in C. elegans are larger in number in comparison to those in mammals, suggesting complexity in the receptor– odorant relationships. Recent studies have shown that the same odorant in different concentration could act on multiple receptors in different neurons to induce attractive or repulsive responses. The ASH neuron is known to be responsible for responding to high concentrations of volatile odorants. Here we characterize a new GPCR, SRX-97. We found that the srx-97 promoter shows expression specifically in the head ASH and tail PHB chemosensory neurons of C. elegans. Further, the SRX-97 protein localizes to the ciliary ends of the ASH neurons. Analysis of CRISPR/based deletion mutants of the srx-97 gene suggest that this gene is involved in the recognition of high concentrations of benzaldehyde. This was further confirmed through rescue and neuronal ablation experiments. Our work gives insight into concentration dependent receptor function in the olfactory system and provides details of an additional molecule that could help the animal navigate its surroundings.

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Metalloprotease cleavage of the N terminus of the orphan G protein–coupled receptor GPR37L1 reduces its constitutive activity

Science Signaling ◽

10.1126/scisignal.aad1089 ◽

2016 ◽

Vol 9 (423) ◽

pp. ra36-ra36 ◽

Cited By ~ 21

Author(s):

James L. J. Coleman ◽

Tony Ngo ◽

Johannes Schmidt ◽

Nadine Mrad ◽

Chu Kong Liew ◽

...

Keyword(s):

G Protein ◽

Cultured Cells ◽

Amino Terminus ◽

Wild Type ◽

Guanine Nucleotide Binding Protein ◽

Inactive Form ◽

In The Wild ◽

Reporter Assays ◽

Guanine Nucleotide Binding ◽

G Protein Coupled

Little is known about the pharmacology or physiology of GPR37L1, a G protein (heterotrimeric guanine nucleotide–binding protein)–coupled receptor that is abundant in the cerebellum. Mice deficient in this receptor exhibit precocious cerebellar development and hypertension. We showed that GPR37L1 coupled to the G protein Gαs when heterologously expressed in cultured cells in the absence of any added ligand, whereas a mutant receptor that lacked the amino terminus was inactive. Conversely, inhibition of ADAMs (a disintegrin and metalloproteases) enhanced receptor activity, indicating that the presence of the amino terminus is necessary for GPR37L1 signaling. Metalloprotease-dependent processing of GPR37L1 was evident in rodent cerebellum, where we detected predominantly the cleaved, inactive form. However, comparison of the accumulation of cAMP (adenosine 3′,5′-monophosphate) in response to phosphodiesterase inhibition in cerebellar slice preparations from wild-type and GPR37L1-null mice showed that some constitutive signaling remained in the wild-type mice. In reporter assays of Gαs or Gαi signaling, the synthetic, prosaposin-derived peptide prosaptide (TX14A) did not increase GPR37L1 activity. Our data indicate that GPR37L1 may be a constitutively active receptor, or perhaps its ligand is present under the conditions that we used for analysis, and that the activity of this receptor is instead controlled by signals that regulate metalloprotease activity in the tissue.

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Multiple kinases phosphorylate the pancreatic cholecystokinin receptor in an agonist-dependent manner

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1993.264.5.g840 ◽

1993 ◽

Vol 264 (5) ◽

pp. G840-G847 ◽

Cited By ~ 4

Author(s):

L. K. Gates ◽

C. D. Ulrich ◽

L. J. Miller

Keyword(s):

Protein Kinase ◽

G Protein ◽

Pancreatic Acinar Cell ◽

Dependent Manner ◽

Receptor Kinase ◽

G Protein Coupled Receptor ◽

Guanine Nucleotide Binding Protein ◽

Permeabilized Cells ◽

High Concentrations ◽

G Protein Coupled

The cholecystokinin (CCK) receptor on the rat pancreatic acinar cell is a guanine nucleotide-binding protein (G protein)-coupled receptor, which was recently demonstrated to be phosphorylated in response to agonist stimulation (Klueppelberg et al., J. Biol. Chem. 266: 17744-17746, 1991). In this work, we establish that this receptor is phosphorylated in response to a variety of homologous and heterologous secretagogues and that these phosphorylation events represent action by more than one protein kinase. One subgroup of kinases includes one or more isotype of protein kinase C (PKC), and is capable of playing a role in homologous and heterologous desensitization. A second subgroup of kinases that acts on the CCK receptor was defined by its resistance to 10 microM staurosporine, which was shown to inhibit all PKC in these cells. The activity of the second group of kinases was observed only in response to occupation of the CCK receptor by high concentrations of native hormone, raising the possibility of a "receptor-specific kinase." Similar to the prototypical kinase, beta-adrenergic receptor kinase (beta-ARK), this activity was inhibited in permeabilized cells by heparin. Furthermore, like this enzyme activity, beta-ARK was shown to be resistant to staurosporine. Based on its action on a G protein-coupled receptor, its activation at high concentrations of native agonist, and its pattern of inhibition, we believe that the staurosporine-insensitive CCK receptor kinase activity represents either beta-ARK or a closely related member of the receptor-specific kinase enzyme family.

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Binding site identification of G protein-coupled receptors through a 3D Zernike polynomials-based method: application to C. elegans olfactory receptors

Journal of Computer-Aided Molecular Design ◽

10.1007/s10822-021-00434-1 ◽

2022 ◽

Author(s):

Lorenzo Di Rienzo ◽

Luca De Flaviis ◽

Giancarlo Ruocco ◽

Viola Folli ◽

Edoardo Milanetti

Keyword(s):

Binding Site ◽

G Protein ◽

Molecular Mechanisms ◽

Model Organism ◽

Olfactory Receptors ◽

G Protein Coupled Receptors ◽

Zernike Polynomials ◽

C Elegans ◽

Shape Complementarity ◽

G Protein Coupled

AbstractStudying the binding processes of G protein-coupled receptors (GPCRs) proteins is of particular interest both to better understand the molecular mechanisms that regulate the signaling between the extracellular and intracellular environment and for drug design purposes. In this study, we propose a new computational approach for the identification of the binding site for a specific ligand on a GPCR. The method is based on the Zernike polynomials and performs the ligand-GPCR association through a shape complementarity analysis of the local molecular surfaces. The method is parameter-free and it can distinguish, working on hundreds of experimentally GPCR-ligand complexes, binding pockets from randomly sampled regions on the receptor surface, obtaining an Area Under ROC curve of 0.77. Given its importance both as a model organism and in terms of applications, we thus investigated the olfactory receptors of the C. elegans, building a list of associations between 21 GPCRs belonging to its olfactory neurons and a set of possible ligands. Thus, we can not only carry out rapid and efficient screenings of drugs proposed for GPCRs, key targets in many pathologies, but also we laid the groundwork for computational mutagenesis processes, aimed at increasing or decreasing the binding affinity between ligands and receptors.

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Non-classical amine recognition evolved in a large clade of olfactory receptors

eLife ◽

10.7554/elife.10441 ◽

2015 ◽

Vol 4 ◽

Cited By ~ 24

Author(s):

Qian Li ◽

Yaw Tachie-Baffour ◽

Zhikai Liu ◽

Maude W Baldwin ◽

Andrew C Kruse ◽

...

Keyword(s):

Biogenic Amines ◽

G Protein ◽

Olfactory System ◽

Olfactory Receptors ◽

G Protein Coupled Receptors ◽

Structural Basis ◽

Trace Amine ◽

G Protein Coupled ◽

Structural Versatility ◽

Amine Detection

Biogenic amines are important signaling molecules, and the structural basis for their recognition by G Protein-Coupled Receptors (GPCRs) is well understood. Amines are also potent odors, with some activating olfactory trace amine-associated receptors (TAARs). Here, we report that teleost TAARs evolved a new way to recognize amines in a non-classical orientation. Chemical screens de-orphaned eleven zebrafish TAARs, with agonists including serotonin, histamine, tryptamine, 2-phenylethylamine, putrescine, and agmatine. Receptors from different clades contact ligands through aspartates on transmembrane α-helices III (canonical Asp3.32) or V (non-canonical Asp5.42), and diamine receptors contain both aspartates. Non-classical monoamine recognition evolved in two steps: an ancestral TAAR acquired Asp5.42, gaining diamine sensitivity, and subsequently lost Asp3.32. Through this transformation, the fish olfactory system dramatically expanded its capacity to detect amines, ecologically significant aquatic odors. The evolution of a second, alternative solution for amine detection by olfactory receptors highlights the tremendous structural versatility intrinsic to GPCRs.

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G protein–coupled receptor kinase 5 (GRK5); guanine nucleotide binding protein, q polypeptide (GNAQ; Gq); histone deacetylase 5 (HDAC5); myocyte enhancing factor 2 (Mef2; D-Mef2)

Science-Business eXchange ◽

10.1038/scibx.2008.703 ◽

2008 ◽

Vol 1 (29) ◽

pp. 703-703

Keyword(s):

G Protein ◽

Histone Deacetylase ◽

Binding Protein ◽

Nucleotide Binding ◽

Guanine Nucleotide ◽

Receptor Kinase ◽

Guanine Nucleotide Binding Protein ◽

Enhancing Factor ◽

Guanine Nucleotide Binding ◽

G Protein Coupled

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Noncanonical scaffolding of Gαi and β-arrestin by G protein–coupled receptors

Science ◽

10.1126/science.aay1833 ◽

2021 ◽

pp. eaay1833

Author(s):

Jeffrey S. Smith ◽

Thomas F. Pack ◽

Asuka Inoue ◽

Claudia Lee ◽

Kevin Zheng ◽

...

Keyword(s):

G Protein ◽

Drug Targets ◽

Direct Interaction ◽

Adaptor Proteins ◽

G Protein Coupled Receptors ◽

Guanine Nucleotide Binding Protein ◽

Signaling Mechanism ◽

Protein Activation ◽

Guanine Nucleotide Binding ◽

G Protein Coupled

Heterotrimeric guanine nucleotide-binding protein (G protein)-coupled receptors (GPCRs) are common drug targets and canonically couple to specific Gα protein subtypes and β-arrestin adaptor proteins. G protein- and β-arrestin-mediated signaling have been considered separable. We show GPCRs promote a direct interaction between Gαi protein subtype family members and β-arrestins, regardless of their canonical Gαi protein subtype coupling. Gαi:β-arrestin complexes bound extracellular signal-regulated kinase (ERK) and their disruption impaired both ERK activation and cell migration, consistent with β-arrestins requiring a functional interaction with Gαi for certain signaling events. These results introduce a GPCR signaling mechanism distinct from canonical G protein activation in which GPCRs cause the formation of Gαi:β-arrestin signaling complexes.

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Faculty Opinions recommendation of Control of feeding behavior in C. elegans by human G protein-coupled receptors permits screening for agonist-expressing bacteria.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1125840.582940 ◽

2008 ◽

Author(s):

Sachdev Sidhu ◽

Raffi Tonikian

Keyword(s):

Feeding Behavior ◽

G Protein ◽

G Protein Coupled Receptors ◽

C Elegans ◽

G Protein Coupled

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Mapping the Heart

Microscopy Today ◽

10.1017/s155192951000043x ◽

2010 ◽

Vol 18 (4) ◽

pp. 6-8

Author(s):

Stephen W. Carmichael

Keyword(s):

Cyclic Adenosine Monophosphate ◽

Adenosine Monophosphate ◽

G Protein Coupled Receptors ◽

Receptor Subtypes ◽

Cardiac Muscle Cells ◽

Guanine Nucleotide Binding Protein ◽

The Common ◽

Guanine Nucleotide Binding ◽

First Time ◽

G Protein Coupled

Some of the receptors on the surface of cardiac muscle cells (cardiomyocytes) mediate the response of these cells to catecholamines by causing the production of the common second messenger cyclic adenosine monophosphate (cAMP). An example of such receptors are the β1- and β2-adrenergic receptors (βARs) that are heterotrimeric guanine nucleotide-binding protein (G protein)-coupled receptors. Selective stimulation of these two receptor subtypes leads to distinct physiological and pathophysiological responses, but their precise location on the surface of cardiomyocytes has not been correlated with these responses. In an ingenious combination of techniques, Viacheslav Nikolaev, Alexey Moshkov, Alexander Lyon, Michele Miragoli, Pavel Novak, Helen Paur, Martin Lohse, Yuri Korchev, Sian Harding, and Julia Gorelik have mapped the function of these receptors for the first time.

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